Rapid and specific RIA of serum estrone sulfate with selective solid phase extraction

Area of Science:

• Endocrinology
• Analytical Chemistry
• Biochemistry

Background:

• Conventional methods for analyzing conjugated steroids, such as estrone sulfate (E1S), involve hydrolysis and chromatographic purification.
• These traditional techniques are time-consuming and labor-intensive, limiting their applicability in rapid diagnostic settings.

Purpose of the Study:

• To develop a simplified, rapid, and reliable assay for the simultaneous evaluation of estrone (E1) and estrone sulfate (E1S) in serum.
• To eliminate the need for hydrolysis and chromatographic purification steps in steroid analysis.

Main Methods:

• Selective solid phase extraction (SPE) using a Bond-Elut C2 cartridge was employed for the isolation of E1 and E1S from serum samples.
• Radioimmunoassay (RIA) with a highly specific antiserum was utilized for the quantification of E1 and E1S.

Main Results:

• The SPE method achieved high recoveries for both estrone (80%) and estrone sulfate (90%).
• The developed RIA demonstrated acceptable accuracy and precision, with intra-assay coefficients of variation ranging from 4.4% to 10.4% and inter-assay coefficients of variation from 6.5% to 13.9%.
• A strong correlation was observed between the proposed method and a conventional enzymatic assay.

Conclusions:

• The developed SPE-RIA method offers a significantly less time-consuming and more reliable approach for evaluating E1 and E1S compared to traditional methods.
• This simplified assay provides a valuable tool for rapid and accurate assessment of E1 and E1S levels in clinical samples.